JP3422558B2 - Three-dimensional sound and heat insulating plate - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to an exhaust manifold heat insulator for an automobile,
The present invention relates to a soundproof and heat insulating plate having a three-dimensional shape.

[0002]

2. Description of the Related Art Conventionally, in an engine room of an automobile, for example, an electronic device for performing engine control, traveling control and the like is arranged together with an engine. Therefore, in order to protect these electronic devices from high heat, an exhaust manifold heat insulator (hereinafter referred to as an insulator) as a heat shield plate is provided. This insulator has a certain space from the exhaust manifold, which is a heat source, and is arranged around the space, and serves as an effective heat shield plate. The insulator is generally fixed to an exhaust manifold which is a vibration source. The exhaust manifold is also a noise source. Therefore, the insulator is a heat insulating and heat insulating plate which is a heat insulating plate and also has a role as a sound insulating material.

[0003]

However, the above-mentioned conventional insulator is one in which a metal plate or a plurality of metal plates are laminated and fixed, or an asbestos sheet or the like is sandwiched therebetween. Therefore, it does not play a sufficient role as a soundproof and heat insulating plate. That is, the conventional insulator may have a high noise level due to the solid-borne sound from the exhaust manifold.

Further, the space between the exhaust manifold and the insulator acts as a resonance box, and the noise from the exhaust manifold is repeatedly reflected in the space, and the noise is amplified. Therefore, the noise value increases due to the insulator. Further, also in a case where an asbestos sheet or the like is sandwiched between one or a plurality of metal plates as a sound absorbing material, the metal plate on the surface reflects noise. Therefore, a sufficient sound absorbing effect cannot be obtained.

Further, as a sound insulating material and a vibration damping material, a vibration damping steel sheet in which a viscoelastic resin is sandwiched between two metal plates has been proposed. However, since the above viscoelastic resin is weak against heat, it is not preferable to install it around a high temperature body such as an exhaust manifold in terms of durability. The present invention is
In view of such problems, it is an object of the present invention to provide a soundproof and heat insulating plate having a three-dimensional shape that is excellent in soundproofing, heat shielding, and durability.

[0006]

The present invention provides a sound insulating and heat insulating plate having a three-dimensional shape such as an insulator, wherein the sound insulating and heat insulating plate is a molded metal substrate, and an inorganic sound absorbing material provided on the surface of the metal substrate. A three-dimensional soundproofing shield characterized by comprising a wire mesh, a metal foil, a silica cloth or a glass cloth, which is arranged on the surface of the inorganic sound absorbing material and fixed on the metal substrate with an interval of 10 to 100 mm with eyelets. On the hot plate.

What is most noticeable in the present invention is that the metal substrate has a pitch of 10 to 100 mm.
It consists of wire mesh, metal foil, silica cloth or glass cloth fixed with eyelets. As the metal plate, for example, a steel plate, an aluminum plate, a stainless plate, an aluminized steel plate or the like is used. The inorganic sound absorbing material is preferably fixed to the metal plate with an adhesive. An inorganic material is preferable as the adhesive. Further, the inorganic fiber preferably has heat resistance.

The inorganic sound absorbing material and the wire mesh, metal foil, silica cloth or glass cloth arranged on the surface of the inorganic sound absorbing material and fixed to the metal substrate with eyelets are excellent in heat resistance and flexibility. Is. The flexibility is necessary not only for fixing the inorganic sound absorbing material to the curved surface, but also for absorbing the sound emitted from the exhaust manifold by the inorganic sound absorbing material without reflecting it. Further, as the material of the wire net, SUS304 is preferable in terms of heat resistance and oxidation resistance. In addition, SUS304 is suitable as the material of the metal foil from the viewpoint of heat resistance and oxidation resistance.

In industrial machinery, a sound absorbing material is fixed to a metal plate with expanded metal, but it is effective as a soundproofing measure, but is not suitable as an automobile part. The reason is that short-fiber non-woven fabrics such as glass wool, rock wool, silica-alumina ceramic fiber, etc., which are usually used as sound absorbing materials, have no practical problem in the case of stationary industrial machines, but they are In addition, in the case of automobile parts used under conditions such as running wind and muddy water, it is not possible to hold the sound absorbing material with something like expanded metal with a high opening ratio, and the sound absorbing material scatters or flows out gradually. Because I will do it. Therefore, wire mesh, metal foil, silica cloth or glass cloth is required to hold the inorganic sound absorbing material.

The wire mesh, metal foil, silica cloth or glass cloth can be fixed by rivets, stud pins,
Although there are methods such as binding with a wire, eyelets are preferable from the viewpoint of durability. The eyelet preferably has a hole diameter of 10 mm or less. This is because, if the hole diameter of the eyelet is larger than 10 mm, sound will pass through that portion and the soundproof effect will be reduced. Next, the fixed portion has a pitch of 10 to 10.
It is preferable to have a spacing of 0 mm. Pitch is 1
If it is less than 0 mm, the fixed portion becomes a sound bridge, and the soundproof effect may be reduced. Further, when the pitch is larger than 100 mm, the inorganic sound absorbing material floats from the metal substrate. Therefore, there is a problem that the soundproof effect is deteriorated by the vibration of the metal substrate.

The inorganic sound absorbing material is preferably an inorganic fiber. The inorganic fiber absorbs noise as follows. That is, the energy of sound that has entered the spaces between the fibers of the inorganic fibers is converted into heat energy due to the viscous resistance of the capillaries, or the energy of the sound that the fibers themselves have entered is converted into heat energy.
Therefore, the inorganic fiber plays a role of a sound absorbing material.

The above-mentioned inorganic fiber absorbs vibration in the following manner. That is, the vibration energy transmitted from the engine to the engine cover is converted into heat energy by the internal friction of the inorganic fibers. Therefore, the inorganic fiber plays a role of a vibration damping material. As the inorganic fiber,
It is preferably ceramic fiber or glass fiber.

The above-mentioned ceramic fiber is one of the inorganic sound absorbing materials which can satisfy the following conditions such as density:
Most common, cheap and safe. Further, the ceramic fiber has excellent heat resistance and durability.
When the heat resistance is not so important, glass fiber is preferable from the viewpoint of cost. As the inorganic fiber, alumina, silica-alumina, glass,
At least one material selected from the group consisting of silica and rock wool is used.

Next, the inorganic sound absorbing material has a thickness of 0.5 mm to 1
It has a thickness of 5 mm and its bulk density is 0.05 g / c.
It is preferably m ^{3 to} 0.5 g / cm ³ . 0.5
If the thickness is less than mm, sound absorption and vibration damping are insufficient, while if it is more than 15 mm, it may not be mounted on the engine in a limited space of the engine room. The bulk density is less than 0.05 g / cm ^3, results in durability issues, greater than 0.5 g / cm ^3, which may cause the sound absorbing bad problem. The sound insulating and heat insulating plate of the present invention exhibits excellent effects as a sound insulating and heat insulating material for high heat and noise generating equipment such as the above-mentioned insulator, exhaust pipe, muffler, turbocharger cover, catalytic converter and the like.

[0015]

In the three-dimensional soundproof and heat-insulating plate of the present invention, a metal substrate, an inorganic sound-absorbing material provided on the surface of the metal substrate, and the above-mentioned wire mesh, metal foil, silica cloth or glass cloth are used. There is. The insulator or the like made of the soundproof and heat insulating plate is installed so that the surface provided with the inorganic sound absorbing material faces the engine or the like. Therefore, noise from the engine or the like is absorbed by the inorganic sound absorbing material and does not propagate to the metal substrate. Therefore, noise is not transmitted to the outside through the metal substrate. Also, the above
On the surface of the sound absorbing material, that is, the sound source side,
Wire mesh fixed with eyelets at intervals of 10 to 100 mm,
Metal foil, silica cloth or glass cloth is placed
It Such wire mesh, silica cloth or glass cloth prevents the soundproof effect from being lowered by the vibration of the metal substrate,
Since the sound on the sound source side is passed through the sound absorbing material, the sound absorbing effect of the inorganic sound absorbing material is extremely effectively exhibited.

Further, the inorganic sound absorbing material has an excellent heat shielding effect. Therefore, the heat generated by the engine or the like can be easily blocked. Further, the sound is converted into heat energy by the vibration of the metal foil, and further, the vibration of the metal foil is absorbed by the inorganic sound absorbing material. In addition, the wire mesh, metal foil, silica cloth or glass cloth supports the inorganic sound absorbing material. Therefore, peeling, scattering, or outflow of the inorganic sound absorbing material is prevented, and the durability is excellent. Further, with the above configuration, a sound insulating and heat insulating plate having a complicated three-dimensional shape can be easily manufactured. As described above, according to the present invention, it is possible to provide a soundproof and heat insulating plate having a three-dimensional shape that is excellent in soundproofing, heat shielding, and durability.

[0017]

【Example】

Example 1 With respect to a three-dimensional soundproof and heat insulating plate according to an example of the present invention,
This will be described with reference to FIGS. 1 and 2. The three-dimensional soundproof and heat shield plate of this example is used as an exhaust manifold heat insulator 1 (hereinafter referred to as an insulator) of an automobile. As shown in FIG. 1, the insulator 1 is composed of a sound insulating and heat insulating plate having a three-dimensional shape. The insulator is a metal substrate 12 formed in the above shape,
The inorganic sound absorbing material 11 disposed on the surface of the metal substrate 12, and the metal substrate 1 disposed on the surface of the inorganic sound absorbing material 11.
2, the metal mesh 10 fixed with rivets 14, the metal foil 30,
It is made of silica cloth 40 or glass cloth 41. In addition, the thing using the wire net 10 was made into the sample 1. Metal foil 30
Was used as the sample 2. The sample using the silica cloth 40 was designated as Sample 3. Sample 4 using the glass cloth 41 was used.

As the metal substrate 12, an aluminum plated steel plate is used. Its thickness is 0.6 mm. The metal substrate 1
2 is provided with an opening portion 13 in advance in a portion to be fixed with eyelets. The wire mesh is SUS304, the wire diameter of which is 0.2 mm and is a 50 mesh plain weave. The metal foil is SUS304 and has a thickness of 0.1 m.
m. The silica cloth 40 or the glass cloth 41 is a plain weave with a thickness of 0.5 mm. Then, as shown in FIG. 1, a plurality of locations are fixed to the metal substrate 12 with rivets 14.

The inorganic sound absorbing material 11 is a layered product of silica-alumina ceramic fiber (trade name; Ibiwool paper, manufactured by Ibiden Co., Ltd.). Inorganic sound absorbing material 1
The thickness of layer 1 is 3 mm. Its bulk density is 0.25g
/ Cm ³ . The inorganic sound absorbing material 11 is provided with an opening portion 16 in advance in a portion where the eyelet is fixed, and at this portion, the metal substrate 12, the wire net 10, the metal foil 30, and the silica cloth 4 are provided.
It is fixed by eyelet with 0 or glass cloth 41.
The manufactured insulator 1 is installed so that the surface provided with the metal net 10, the metal foil 30, the silica cloth 40, or the glass cloth 41 faces the exhaust manifold. Next, the relationship between the pitch of the eyelet fixing portion 14 of the sample 1 and noise was as shown in FIG.

Next, the function and effect of this example will be described. The insulator 1 is installed so that the surface provided with the wire net 10, the metal foil 30, the silica cloth 40, or the glass cloth 41 faces the exhaust manifold. Therefore, the noise from the exhaust manifold passes through the wire net 10, the metal foil 30, the silica cloth 40, or the glass cloth 41, is absorbed by the inorganic sound absorbing material 11, and the attenuated noise reaches the metal substrate 12. The sound reflected from the substrate 12 is further absorbed by the inorganic sound absorbing material 11 and reduced.

Therefore, in the structure of this example, the space between the exhaust manifold and the insulator plays the role of a resonance box, and the noise from the exhaust manifold is repeatedly reflected in the space, and the noise is amplified. , Suppress. Further, the vibration propagating from the exhaust manifold to the insulator 1 is absorbed by the inorganic sound absorbing material 11. Therefore, it is possible to prevent new noise from being generated by using the insulator as the acoustic radiation surface.

Further, the inorganic sound absorbing material 11 uses ceramic fibers having an excellent heat shielding effect. Therefore, the heat generated from the exhaust manifold can be easily blocked. Further, the ceramic fiber is a material having excellent heat resistance and can withstand high heat conditions around the exhaust manifold. Also, 1 wire mesh for ceramic fiber
0, the metal foil 30, the silica cloth 40 or the glass cloth 41 is arranged, and the metal mesh 10, the metal foil 30, the silica cloth or the glass cloth supports the ceramic fiber.
Therefore, it is possible to prevent the ceramic fibers from peeling, scattering, or flowing out from the metal substrate 12, and therefore the insulator of this example has excellent durability. Further, with the above configuration, it is easy to manufacture a sound insulating and heat insulating plate having a complicated three-dimensional shape. As described above, according to this example, it is possible to provide a soundproof and heat-insulating plate having a three-dimensional shape that is excellent in soundproofing, heat shielding, and durability.

In this example, as shown in FIGS. 5 to 6 and Table 1, the transfer function characteristics and the loss coefficient at each resonance frequency of the soundproof and heat insulating plate (Sample 1) according to the present invention were measured. For comparison, the comparison was made with the conventional product (Comparative Example C1). The configurations of the sample 1 of this example and the comparative example C1 are shown in FIGS.
Shown in. The soundproof and heat shield plate 1 of the sample 1 is as shown in FIG.
The metal substrate 12, the inorganic sound absorbing material 11, and the wire netting 10 are fixed by eyelets 14 and manufactured using the same material as in the first embodiment.

As shown in FIG. 3, the soundproof and heat shield plate 2 of Comparative Example C1 is formed by joining two aluminum-plated steel plates 21 and 22 by spot welding 14. The aluminum-plated steel plate 21 has a thickness of 0.6 mm. The aluminum-plated steel plate 22 has a thickness of 0.4 mm. Then, in both samples, the surface drawn on the upper side of the figure faces the sound source. The results of measuring the transfer function characteristics of these samples are
5 and 6 show the results of measuring the loss coefficient at each resonance frequency in Table 1.

As can be seen from FIGS. 5 and 6, the transfer function characteristic curve of the sample 1 according to the present invention has a gentler peak end than that of the conventional sample C1. This means that the vibration energy propagating in the sample 1 is attenuated earlier than in the comparative example C1. That is, the vibration energy is absorbed in the sample 1. Therefore, the sample 1 is less likely to transmit noise. Further, as is known from Table 1, the loss coefficient at each resonance frequency of Sample 1 is lower than that of Comparative Example C1.
About 15 times larger. Therefore, the above effect can be more clearly known. That is, it can be seen that the product of the present invention has a structure in which it is difficult to transmit noise to the outside.

[0026]

[Table 1]

In this example, as shown in Table 2, an insulator was produced by using the soundproof and heat insulating plate according to the present invention and the conventional heat insulating plate. Then, for comparison and control, these were mounted on an actual engine, and the noise propagated to the outside through the insulator was measured. The soundproof and heat-shielding plate used in this example has the same structure as Sample 1, Sample 2, Sample 3, Sample 4 and Sample 1 as samples according to the present invention. And the sample 5 fixed on. As a comparative example, sample C1 was used. In addition, an example without using an insulator is sample C
It was set to 2. The engine used for the measurement was a 2-liter, 4-cylinder diesel engine with a rotation speed of 3000 r.
p. It was driven at m. A noise meter was installed at a position 50 cm away from the insulator, and the noise characteristics were measured. The results are shown in Table 2.

As is known from Table 2, the noise characteristics of Samples 1 and 2 according to the present invention are lower than those of Comparative Examples C1 and C2. That is, in the comparative example C1 of the conventional product, the sound amplified by the resonance in the space between the exhaust manifold and the insulator propagates through the insulator and is emitted to the outside. Therefore, rather than the comparative example C2 in which the insulator is not provided, Noise characteristics are large. However, the soundproof and heat insulating plate of the present invention absorbs the noise generated from the engine by the inorganic sound absorbing material provided on the side facing the engine. In addition, because of the above-mentioned inorganic sound absorbing material, it is difficult for vibration to propagate through the soundproof and heat insulating plate. Furthermore, the wire mesh allows noise to pass through and the noise to be absorbed by the inorganic sound absorbing material. Therefore, in the product of the present invention, it is difficult to transmit noise to the outside, and further, the vibration transmitted from the exhaust manifold to the insulator does not cause the engine cover to become a sound emission surface and become a new noise generation source.

[0029]

[Table 2]

As a comparative example of the soundproof and heat shield plate used in this example,
A sample (C6) using a metal expanded metal having a thickness of about 1 mm for 3 mesh instead of the wire net 10 was vibrated (3.5 g-33 Hz) for 10 hours by a vibration tester.
When the weight loss before and after the test was measured, the sample of the present invention showed no change at 0% weight loss, but Comparative Example C
In the sample of No. 3, a part of the inorganic sound absorbing material 11 was peeled off from the opening of the expanded metal, and the weight loss was 6.8%.

[Brief description of drawings]

FIG. 1 is a front view of an insulator according to a first embodiment.

FIG. 2 is a sectional view of FIG.

FIG. 3 is a sectional view of comparative example C1.

FIG. 4 is a diagram showing the relationship between the pitch of the eyelet fixing portion and noise in the first embodiment.

5 is a diagram showing a transfer function characteristic of Sample 1. FIG.

FIG. 6 is a diagram showing a transfer function characteristic of Comparative Example C1.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Insulator, 10 ... Wire mesh, 11 ... Inorganic sound-absorbing material, 12 ... Metal substrate, 13 ... Opening part previously provided in the metal substrate for fixing eyelet 14 ... Eyelet Fixing part 16: Opening part provided in advance in the inorganic sound absorbing material for fixing eyelets

─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) F01N ⁷ /00-7/20 C04B 32/00-32/02 F02B 77/00-77/14

Claims (4)

(57) [Claims] 1. A sound-insulating heat-insulating plate having a three-dimensional shape such as an exhaust manifold heat insulator of an automobile, wherein the sound-insulating heat-insulating plate is a molded metal substrate, and an inorganic sound absorbing material provided on the surface of the metal substrate. It is arranged on the surface of the inorganic sound absorbing material and has a pitch of 10 to 100 on the metal substrate.
A three-dimensional soundproof and heat-insulating plate, which is made of wire mesh, metal foil, silica cloth, or glass cloth fixed with eyelets at an interval of mm . 2. The three-dimensional soundproof and heat shield plate according to claim 1, wherein the inorganic sound absorbing material is made of an inorganic fiber. 3. The inorganic fiber according to claim 2 ,
A soundproof and heat-insulating plate having a three-dimensional shape, which is made of one or more materials selected from the group consisting of alumina, silica-alumina, glass, silica, and rockwool. 4. The inorganic sound absorbing material according to claim 3 ,
A three-dimensional soundproof and heat shield plate having a thickness of 0.5 mm to 15 mm and a bulk density of 0.05 g / cm ^{3 to} 0.5 g / cm ³ .